Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-1_4/rev/6673f63c5835
Author: Luke Chang <lchang@mozilla.com>
Desc: Merge pull request #23121 from luke-chang/987496_v1.4_hindi_input_method

Bug 987496 - Adding Hindi Input Method for B2G

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https://hg.mozilla.org/integration/gaia-1_4/rev/0bf8577a1f92
Author: Luke Chang <lchang@mozilla.com>
Desc: Bug 987496 - Adding Hindi Input Method for B2G

Cherry-pick from 7882bd086a460ff07b170ed45a1cf8981f4d0f72

Conflicts:

  build/config/keyboard-layouts.json
Bumping manifests a=b2g-bump